B.

TECH HONS THESIS

SANITARY FITTING AND FIXTURES

BY

USMAN ZAFAR

14M2-115114

Supervisor

ENG. WAHEED AKHTAR

DEPARTMENT OF CIVIL ENGINEERING

PRESTON UNIVERSITY (ISLAMABAD CAMPUS)

PAKISTAN

2018
 CERTIFICATE
This is to certify that USMAN ZAFAR has satisfactorily completed the thesis for
Graduate in civil Technology during the year 2018.

This thesis “SANITARY FITTING AND FIXTURE” is submitted to the Preston

University Islamabad Campus in partial fulfillment of the requirement for the
degree of B.TECH (HONS) in civil Technology.

____________ ____________

Supervisor External

Engr. Waheed Akhtar

Date: ___________
 PRESTON UNIVERSITY

(ISLAMABAD CAMPUS)

UNDERTAKING
The substance of this thesis is the original work of the undersigned and due
reference and acknowledgement has been made, where necessary, to the works
of others. No part of this thesis has been already accepted for any degree and it is
not being currently submitted in candidature for any degree. No part of the study
will be published without prior permission of the Preston University (Islamabad
Campus).

Name: Usman Zafar

Regd No : 14M2-115114

_________________

Signature of Student
 ACKNOWLEDGEMENT
All praises to Almighty Allah who bestowed upon me His blessing. This enabled
me to accomplish this assignment successfully.

I owe sincere gratitude to my supervisor, Eng., Waheed Akhtar who extended

every possible cooperation, guidance and advice during the completion of this
work, without whose cooperation this material can never be materialized.

Last but not least, special thanks to my family, friends and colleagues who always
stood beside me; their kind help and company enabled me to fulfill this
obligation.

AUTHOR
 DEDICATION

TO

MY BELOVED PARENTS

Without whom support, guidance, efforts and prayers I would

Not has been the shadow of my present self

 ABSTRACT

The elements of sanitary science which are essential to sanitary

fitting & fixture are briefly outlined, and in the historical notes it
is shown how the filthy habits of the people in early times led to
direful epidemics of plague.

An attempt has been made in this treatise to explain the

fundamentals of sanitary engineering.
Table of Contents

CHAPTER 1................................................................................................................................................15

INTRODUCTION.........................................................................................................................................15
1.1 GENERAL:.......................................................................................................................................15
1.2 Purpose of sanitation:....................................................................................................................15
1.3 Principles of sanitation:.................................................................................................................16
1.4 Sanitary projects:.................................................................................................................................16
1.5 Projects drawings:...............................................................................................................................17

CHAPTER 2.................................................................................................................................................19

COLLECTION AND CONVEYANCE OF REFUSE.............................................................................................19

2.1 General:...............................................................................................................................................19
2.2 Methods of carrying refuse:................................................................................................................19
2.2.1 Conservancy System:........................................................................................................................19
1. Cost:...................................................................................................................................................20
2. Design of building:.............................................................................................................................20
3. Insanitary condition:..........................................................................................................................20
4. Labour problem:................................................................................................................................20
5. Land of disposal:................................................................................................................................21
6. Night soil carts:..................................................................................................................................21
Open drains:..............................................................................................................................................21
Pollution of water:.....................................................................................................................................21
2.2.2 Water carriage System:....................................................................................................................21
Compact design:........................................................................................................................................22
Hygienic:....................................................................................................................................................22
Land for treatment works:.........................................................................................................................22
Method of treatment:...............................................................................................................................22
Water Requirement:..................................................................................................................................23
CHAPTER 3.................................................................................................................................................25

Pipes used for Water supply......................................................................................................................25

3.1Introduction:.........................................................................................................................................25
3.2History:.................................................................................................................................................26
3.3Systems:...............................................................................................................................................27
3.4Material for pipes:................................................................................................................................28
3.4.1 Steel pipe:.........................................................................................................................................29
3.4.2 Copper pipe:.....................................................................................................................................30
3.4.3 Plastic Pipe:.......................................................................................................................................30

CHAPTER 4.................................................................................................................................................32

Pipe Fittings...............................................................................................................................................32
4.1Introduction:.........................................................................................................................................32
4.2 Elbow:..................................................................................................................................................32
An elbow is installed between two lengths of pipe (or tubing) to allow a change of direction, usually
a 90° or 45° angle; 22.5° elbows are also available. The ends may be machined for butt
welding, threaded (usually female), or socketed. When the ends differ in size, it is known as a
reducing (or reducer) elbow..............................................................................................................32

........33
A 90º elbow, also known as a "90 bend", "90 ell" or "quarter bend", attaches readily to plastic,
copper, cast iron, steel, and lead, and is attached to rubber with stainless-steel clamps. Other
available materials include silicone, rubber compounds, galvanized steel, and nylon. It is primarily
used to connect hoses to valves, water pumps and deck drains. A 45º elbow, also known as a "45
bend" or "45 ell", is commonly used in water-supply facilities, food, chemical and electronic
industrial pipeline networks, air-conditioning pipelines, agriculture and garden production, and
solar-energy facility piping.................................................................................................................33
4.3 Union:..................................................................................................................................................34
A union, similar to a coupling, allows the convenient future disconnection of pipes for maintenance
or fixture replacement. In contrast to a coupling requiring solvent welding, soldering, or rotation
(for threaded couplings), a union allows easy connection and disconnection, multiple times if
needed. It consists of three parts: a nut, a female end and a male end. When the female and male
ends are joined, the nut seals the joint by pressing the two ends tightly together. Unions are a type
of very compact flange connector.....................................................................................................34
Electric unions, with dielectric insulation, separate dissimilar metals (such as copper and galvanized
steel) to prevent galvanic corrosion. When two dissimilar metals are in contact with an electrically
conductive solution (ordinary tap water is conductive), they form an electrochemical couple which
generates a voltage by electrolysis....................................................................................................34
When the metals are in direct contact with each other, the electric current from one to the other
also moves metallic ions from one to the other; this dissolves one metal, depositing it on the other.
A dielectric union breaks the electrical path with a plastic liner between its halves, limiting galvanic.
...........................................................................................................................................................34
4.4 Nipple:.................................................................................................................................................34
4.5 Reducer:..............................................................................................................................................35
4.6 Coupling:..............................................................................................................................................36
4.7 Tee:......................................................................................................................................................36
Tee, the most common pipe fitting, is used to combine (or divide) fluid flow. It is available with
female thread sockets, solvent-weld sockets or opposed solvent-weld sockets and a female-
threaded side outlet. Tees can connect pipes of different diameters or change the direction of a
pipe run, or both. Available in a variety of materials, sizes and finishes, they may also be used to
transport two-fluid mixtures.Tees may be equal or unequal in size of their three connections, with
equal tees the most common............................................................................................................36
4.8Diverter tee:.................................................................................................................................37
4.9 Cross:...........................................................................................................................................37
Crosses, also known as four-way fittings or cross branch lines, have one inlet and three outlets (or
vice versa), and often have solvent-welded socket or female-threaded ends. Cross fittings may
stress pipes as temperatures change, because they are at the center of four connection points. A
tee is steadier than a cross; it behaves like a three-legged stool, and a cross behaves like a four-
legged stool. Geometrically, any three non-collinear points can self-consistently define a plane;
three legs are inherently stable, whereas four points overdetermine a plane, and can be
inconsistent, resulting in physical stress on a fitting..........................................................................37
4.10 Cap:............................................................................................................................................38
Caps, usually liquid- or gas-tight, cover the otherwise open end of a pipe. A cap attaches to the
exterior of a pipe, and may have a solvent-weld socket end or a female-threaded interior. The
 exterior of an industrial cap may be round, square, rectangular, U- or I-shaped, or may have a
handgrip. If a solvent-weld cap is used to provide for a future connection point, several inches of
pipe must be left before the cap; when the cap is cut off for the future connection, enough pipes
must remain to allow a new fitting to be glued onto it......................................................................38
4.11 Plug:...........................................................................................................................................38
A plug fits inside the pipe segment or fitting.....................................................................................38
4.12 Barb:..........................................................................................................................................38
5.2Connection methods:.......................................................................................................................40
Threaded steel pipe is widely used in buildings to convey natural gas or propane fuel, and is a
popular choice in fire sprinkler systems due to its resistance to mechanical damage and high heat.
Threaded steel pipe may still be used in high-security locations; because it is more resistant to
vandalism, more difficult to remove, and its scrap value is lower than copper or brass Assembling
threaded steel pipe takes skill and planning to allow lengths of pipe to be screwed together in
sequence. Most threaded-pipe systems require the use of strategically located pipe-union fittings in
final assembly. Threaded steel pipe is heavy, and requires adequate attachment to support
surfaces. Despite its thick walls steel pipe is no longer preferred for conveying drinking water,
because corrosion can cause leakage especially at threaded joints, and deposits on internal surfaces
will eventually restrict flow...............................................................................................................41
5.4Solvent welding:...........................................................................................................................41
A solvent is applied to PVC, CPVC, ABS or other plastic piping to partially dissolve and fuse the
adjacent surfaces of piping and fitting. Solvent welding is usually used with a sleeve-type joint to
connect pipe and fittings made of the same (or compatible) material..............................................41

.........................................................................41
Unlike metal welding, solvent welding is relatively easy to perform (although care is needed to
make reliable joints). Solvents typically used for plastics are usually  and may
be carcinogenic and flammable, requiring adequate ventilation......................................................41
5.5Soldering:......................................................................................................................................42
Make a solder connection, a chemical flux is applied to the inner sleeve of a joint and the pipe is
inserted. The joint is then heated using a propane or MAPP gas torch, solder is applied to the
heated joint and the molten solder is drawn into the joint by capillary action as the flux vaporizes.
"Sweating" is a term sometimes used to describe the soldering of pipe joints.................................42

.........................................................................................42
Where many connections must be made in a short period of time (such as plumbing of a new
building), soldering is quicker and less expensive joinery than compression or flare fittings. A degree
of skill is needed to make a number of reliable soldered joints quickly. If flux residue is thoroughly
cleaned, soldering can produce a long-lasting connection at low cost. However, the use of an open
flame for heating joints can present fire and health hazards to building occupants, and requires
adequate ventilation.........................................................................................................................42
5.6 Welding:......................................................................................................................................42

.....................................................43
Adequate ventilation is essential to remove metal fumes from welding operations, and personal
protective equipment must be worn. Because the high temperatures during welding can often
generate intense ultraviolet light, dark goggles or full face shields must be used to protect the eyes.
Precautions must also be taken to avoid starting fires caused by stray sparks and hot welding
debris.................................................................................................................................................43
5.7 Compression fittings:...................................................................................................................43
Compression fittings (sometimes called "lock-bush fittings") consist of a tapered, concave conical
seat; a hollow, barrel-shaped compression ring (sometimes called a ferrule); and a compression nut
which is threaded onto the body of the fitting and tightened to make a leakproof connection. They
are typically made of brass or plastic, but stainless steel or other materials may be used...............43

...........................................................................................................................................................44
5.8 Flare fittings:................................................................................................................................44
Flared connectors should not be confused with compression connectors, with which they are
generally not interchangeable. Lacking a compression ring, they use a tapered conical shaped
connection instead. A specialized flaring tool is used to enlarge tubing into a 45º tapered bell shape
matching the projecting shape of the flare fitting. The flare nut, which had previously been installed
over the tubing, is then tightened over the fitting to force the tapered surfaces tightly together.
Flare connectors are typically made of brass or plastic, but stainless steel or other materials may be
used...................................................................................................................................................44

..........................................44
 Although flare connections are labor-intensive, they are durable and reliable. Considered more
secure against leaks and sudden failure, they are used in hydraulic brake systems, and in other
high-pressure, high-reliability applications........................................................................................45
5.9 Flange fittings:.............................................................................................................................45
Flange fittings are generally used for connections to valves, inline instruments or equipment
nozzles. Two surfaces are joined tightly together with threaded bolts, wedges, clamps, or other
means of applying high compressive force. Although a gasket, packing, or O-ring may be installed
between the flanges to prevent leakage, it is sometimes possible to use only special grease or
nothing at all (if the mating surfaces are sufficiently precisely formed). Although flange fittings are
bulky, they perform well in demanding applications such as large water supply
networks and hydroelectric systems.................................................................................................45

...........................................................................................................................................................45
A weld neck flange is joined to a piping system by butt welding. Although its long neck (or hub)
makes it expensive, it reduces mechanical stress on piping by distributing stress between the base
of the flange and the wall at the weld. Turbulence and erosion are reduced due to the matching
size of the pipe and flange a socket flange appears similar to a slip-on flange, but its bore is counter-
bored to accept pipe. A fillet weld around the hub of the flange attaches the flange to the pipe,
with an interval weld added in high-stress applications. It is most frequently used in high-pressure
systems, such as hydraulic and steam lines.......................................................................................45
A lap-joint flange is similar to a slip-on, with room at the intersection of the bore and the flange
face for a lap stub end. The face of the stub end conforms to the gasket face of the flange. It is used
where sections of piping need to be dismantled quickly and easily for inspection or replacement,.46
5.10 Mechanical fittings:........................................................................................................................46
Manufacturers such as Victaulic and Grinnell produce sleeve-clamp fittings which are replacing
many flange connections. They attach to the end of a pipe segment via circumferential grooves
pressed (or cut) around the end of the pipe to be joined. They are widely used on larger steel pipes,
and can also be used with other materials........................................................................................46
 ............................................................46
The chief advantage of these connectors is that they can be installed after cutting the pipe to length
in the field. This can save time and considerable expense compared to flange connections, which
must be factory- or field-welded to pipe segments. However, mechanically fastened joints are
sensitive to residual and thickness stresses caused by dissimilar metals and temperature changes A
grooved fitting, also known as a grooved couplinghas four elements: grooved pipe, gasket, coupling
housing, and nuts and bolts. The groove is made by cold-forming (or machining) a groove at the end
of a pipe.............................................................................................................................................46
A gasket encompassed by coupling housing is wrapped around the two pipe ends, with the coupling
engaging the groove; the bolts and nuts are tightened with a socket or impact wrench. The installed
coupling housing encases the gasket and engages the grooves around the pipe to create a
leakproof seal in a self-restrained pipe joint. There are two types of grooved coupling; a flexible
coupling allows a limited amount of angular movement, and a rigid coupling does not allow
movement and may be used where joint immobility is required (similar to a flange or welded joint).
...........................................................................................................................................................47
CHAPTER 1

INTRODUCTION

1.1 GENERAL:

After the water that has been made valuable from well laid and
properly executed water supply project has been consumed, it
has to be suitably disposed of. The other wastes from the society
are also to be carried and disposed of at suitable places so as to
protect the public health.

The sanitary projects require careful thinking and

planning. A sanitary scheme is not so simple as a water supply
scheme.it requires many factors to be taken into account before a
particular line of treatment is recommemded.The importance of
this branch of engineering is gradually increasing day by day and
attempts are being made to simply the process of water disposal.

The day to day consumption of water reduces the

available quota of natural water. This factor has led the scientists
to find out ways and means of procuring fresh portable water.

The first remedy to increase the quota of natural

water was the conversion of sea water into potable water no
satisfactory method of such conversion has yet been found out.
Various methods of desalination such as flash evaporation,
freezing, electro dialysis ultra-filtration through plastic films etc.
are tried. Thus chemicals engineers are at present engaged in
converting sea water economicaly into fresh water so as to obtain
a good source of water supply for area located nearby sea.
1.2 Purpose of sanitation:

The main purpose of sanitation is to maintain such

environments as will not affect the public health in general. Thus
sanitation aims at the creation of such conditions of living which
will not result into serious breakout of epidemic or in other words
it is a preventive measure for the preservation of health of
community in general and individual in particular.it is to be noted
that the word health indicates the physical and mental soundness
of human body such that it is in a position to discharge its daily
routine functions.

1.3 Principles of sanitation:

Following are the some of the fundamental or rather is

dealprinciples of sanitation which, if observed, result in better
living conditions:

• Collection and conveyance

• Interior decoration

• Orientation of building

• Prevention of dampness

• Supply of water

• Treatment of waste

1.4 Sanitary projects:

The sanitary projects are preceded by the water supply
schemes and before the project is final various important points
are to be considered. It is the usual practice to give the
advantage of sanitary project in stages forthis purpose the locality
is divided into suitable zones and one by one zone is taken for the
installation of sanitary facilities.

Following are the some points of importance in any public

sanitary project:

• Financial aspect

• Population

• Present methods of disposal

• Quality of sewage

• Rainfall

• Rate of sewage

• Sources of sewage
1.5 Projects drawings:
These are similar to prepared in case of water supply schemes.
The drawings are prepared on convenient scales to serve various
purposes such as illustrating the scheme, deciding the stages of
adopting the projects, guiding the supervising staff during
construction etc. Following drawing is usually prepared.

1- Contour plans of the area

2- Detailed drawings of all units of the project

3- Diagram of proposed treatment methods

4- Site plan showing location of scheme

5- Topographical map.
CHAPTER 2

COLLECTION AND CONVEYANCE OF REFUSE

2.1 General:

The solid and liquid waste is to be properly collected and conveyed at suitable
spots for treatment and disposal. The cost of collection and conveyance of refuse
forms a major formed in any sanitary system should be rapidly, conveniently and
safety carried to its disposal site so as to maintain a clean environment.

2.2 Methods of carrying refuse:

Following are the two methods which are employed for the collection and
disposal of refuse of a locality:
• Conservancy system

• Water carriage system

2.2.1 Conservancy System:

In this system the different types of refuse are collected separately and then each
type is carried and suitably disposed of.

The garbage or dry refuse is collected from roads and streets in

pans or baskets. It is then conveyed by carts Trucksetc. to some suitable place.
The garbage is separated into two categories namely flammable and inflammable
matters. The former is burnt into incinerators and the latter is buried into low
lying areas for the reclamation of soil.

The night soil is collected in pans from lavatories and sewage is

carried by the labour in carts trucks etc.

The storm water and sullage are collected and conveyed

separately by closed or open channels. They are discharged in natural rivers or
streams.

The conservancy system is out date at present for modern cities. It

is however, adopted for small towns, villages, undeveloped areas of big cities etc.
where there is scarcity of water for the adoption of water carriage system.

Following are the disadvantages of conservancy system:-

1. Cost:
The system seems to be cheap in the beginning but its maintenance and
establishment costs are very high.

2. Design of building:
In this system lavatories are to be constructed separate from the main
building is therefore, does not permit compact design of the structure.

3. Insanitary condition:
The decomposition of sewage starts about 4 to 5 hours after its
production. This fact leads to the development of insanitary conditions
around the residential building as it is practicable to remove sewage only
once in 24 hours or so.
 4. Labour problem:
This system entirely depends on the mercy of labour and if labour goes on
strike due to any reason, the public health is put into great danger.

5. Land of disposal:
The sewage, especially the night soil, requires considerable land for its
disposal.

6. Night soil carts:

It is highly undesirable to allow night soil carts to pass through main roads
of the city.

Open drains:
If storm water and silage are carried in open drains it may result in
insanitary conditions.

Pollution of water:
There are chances or the liquid wastes from the lavatories to be soaked
into the ground.In such case the under ground supply of water will be
polluted.

2.2.2 Water carriage System:

In this system, water is used as medium to convey the sewage to the point of
its treatment or final disposal. The quantity of water to be mixed with solid matter
is quite sufficient and dilution ratio of solid matter with water is so great that the
mixture behaves more or less like water.The sewage is conveyed is suitably
designed and maintained sewers.IN this system the garbage is collected and
conveyed as in case of conservancy system.The storm water may be carried
separately or may be allowed to flow with the sewage.

The initial cost of the installation of water carriage system is

very high and it becomes difficult to adopt it when the financial condition of the
area is very poor. However, the water carriage system is the modern method of
conveyance of sewage and it is to be recommended wherever possible.

Following are the advantages claimed by water carriage system

of conveyance.

Compact design:
The system permits compact design of the building as lavatories can be
accommodated in any part of the building.

Hygienic:
It is hygienic in nature as the night soil foul matter etc., are carried in this
system in closed conduits. The risk of outbreak of epidemic is greatly
reduced.

Land for treatment works:

The area of land required for treatment plant and sewage disposal
in this system is smaller than that required in case of conservancy system.

Method of treatment:
When this system is adopted it becomes easier to apply modern methods
of sewage treatment. The sewage from the entire area can be carried to
 the treatment plant and after the proper treatment it can be suitably
disposed of.

Water Requirement:
It is said that the system requires more water for flushing of
solid matter. But in practice no considerable amount of water is required
for the functioning of this system except the usual water supply.

S.NO Conservancy system Water carriage system

1 It does not permit compact design It permits compact design of

of structure. structure.
2 It is laid above the ground.
It is necessarily laid below the
ground.
3 It requires small quantity of water
to extent of 30 to 40 liters per capita It requires the quantity of water
per day. about 100 to 200 liters per capita per
4 day.
There exists putrefaction.
There is no chance for putrefaction
There is absence of segregation
5 There is presence of segregation.

COMPARISON BETWEEN CONSERVANCY SYSTEM AND WATER CARRIAGE SYSTEM

TABLE 2-1
The use of filtered processed water for the flushing of closets and cleaning of
small sewer lines is appreciably high in this system/For instance a typical flush
toilet will contaminate each year about 60,000 liters of fresh water to move a
mere 800 liters of body waste. Thus valuable fresh water is mixed with the body
wastes having high potential and then we pay dearly to separate them again at
the load on treatment plant pumping station etc. is increased and its result in high
investment and recurring costs.
CHAPTER 3

Pipes used for Water supply

3.1Introduction:
Plumbing is any system that conveys fluids for a wide range of applications.
Plumbing uses pipes, valves, plumbing fixtures, tanks, and other apparatuses to
convey fluids. Heating and cooling (HVAC), waste removal, and water delivery are
among the most common uses for plumbing, but it is not limited to these
applications. The word derives from the Latin for lead, plumber, as the first
effective pipes used in the Roman era were lead pipes
In the developed world, plumbing infrastructure is critical to public health and
sanitation. Boilermakers and pipefitters are not plumbers, although they work
with piping as part of their trade, but their work can include some plumbing .

3.2History:
Plumbing originated during ancient civilizations such as the Greek, Roman,
Persian, Indian and Chinese cities as they developed public baths and needed to
provide potable water and wastewater removal for larger numbers of
people. Standardized earthen plumbing pipes with broad flanges making use
of asphalt for preventing leakages appeared in the urban settlements of the Indus
Valley Civilization by 2700 BC. The Romans used lead pipe inscriptions to prevent
water theft. The word plumber dates from the Roman
Empire. The Latin for lead is plumbum. Roman roofs used lead in conduits and
drain pipes and some were also covered with lead, lead was also used
for piping and for making baths.

Plumbing reached its early apex in ancient Rome, which saw

the introduction of expansive systems of aqueducts, tile wastewater removal, and
widespread use of lead pipes.With the Fall of Rome both water supply and
sanitationstagnated—or regressed—for well over 1,000 years. Improvement was
very slow, with little effective progress made until the growth of modern densely
populated cities in the 1800s. During this period, public health authorities began
pressing for better waste disposal systems to be installed, to prevent or
control epidemics of disease
Most large cities today pipe solid wastes to sewage treatment plants in order to
separate and partially purify the water, before emptying into streams or other
bodies of water. For potable water use, galvanized iron piping was commonplace
in the United States from the late 1800s until around 1960. After that period,
copper piping took over, first soft copper with flared fittings, then with rigid
copper tubing utilizing soldered fittings.
The use of lead for potable water declined sharply after World War II because of
increased awareness of the dangers of lead poisoning. At this time, copper piping
was introduced as a better and safer alternative to lead pipes.

3.3Systems:
The major categories of plumbing systems or subsystems are:

 potable cold and hot tap water supply

 plumbing drainage venting
 sewage systems and septic systems with or without hot water heat
recycling and gray water recovery and treatment systems
 Rainwater, surface, and subsurface water drainage
 fuel gas piping
 hydroids, i.e. heating and cooling systems utilizing water to transport
thermal energy, as in district heating systems, like for example the New York
City steam system
3.4Material for pipes:
The material with which a pipe is manufactured is often the basis for choosing a
pipe. Materials used for manufacturing pipes include:

 Carbon (CS) and galvanized steel
 Impact-tested carbon steel (ITCS)
 Low-temperature carbon steel (LTCS)
 Stainless steel (SS)
 Malleable iron
 Non-ferrous metals (includes copper, Inconel, oncology and cupronickel)
 Non-metallic (includes acrylonitrile butadiene styrene (ABS), fibre-
reinforced plastic (FRP), polyvinyl chloride (PVC), high-density
polyethylene (HDPE) and toughened glass)
 Chrome-molybdenum (alloy) steel — Generally used for high-temperature
service
He bodies of fittings for pipe and tubing are most often the same base material as
the pipe or tubing connected: copper, steel, PVC, chlorinated polyvinyl
chloride (CPVC) or ABS. Any material permitted by the plumbing, health, or
building code (as applicable) may be used, but it must be compatible with the
other materials in the system, the fluids being transported and the temperature
and pressure inside (and outside) the system. Brass or bronze fittings are common
in copper piping and plumbing systems. Fire hazards, earthquake resistance and
other factors also influence the choice of fitting materials.

3.4.1 Steel pipe:

Galvanized steel potable water supply and distribution pipes are commonly found
with nominal pipe sizes from 3⁄8 inch (9.5 mm) to 2 inches (51 mm). It is rarely
used today for new construction residential plumbing. Steel pipe has National
Pipe Thread  standard tapered male threads, which connect with female tapered
threads on elbows, tees, couplers, valves, and other fittings. Galvanized steel
(often known simply as "gal" or "iron" in the plumbing trade) is relatively
expensive, and difficult to work with due to weight and requirement of a pipe
threaded. It remains in common use for repair of existing "gal" systems and to
satisfy building code non-combustibility requirements typically found in hotels,
apartment buildings and other commercial applications. It is also extremely
durable and resistant to mechanical abuse. Black lacquered steel pipe is the most
widely used pipe material for fire sprinklers and natural gas.
Most typical single family home systems won't require supply piping larger
than 3⁄4 inch (19 mm) due to expense as well as steel piping's tendency to become
obstructed from internal rusting and mineral deposits forming on the inside of the
pipe over time once the internal galvanizing zinc coating has degraded. In potable
water distribution service, galvanized steel pipe has a service life of about 30 to
50 years, although it is not uncommon for it to be less in geographic areas with
corrosive water contaminants

3.4.2 Copper pipe:

Copper pipe and tubing was widely used for domestic water systems in the latter
half of the twentieth century. Demand for copper products has fallen due to the
dramatic increase in the price of copper, resulting in increased demand for
alternative products including PEX and stainless steel.
3.4.3 Plastic Pipe:
Plastic pipe is in wide use for domestic water supply and drain-waste-vent (DWV)
pipe. Principal types include: Polyvinyl chloride (PVC) was produced
experimentally in the 19th century but did not become practical to manufacture
until 1926, when Waldo Simon of BF Goodrich Co. developed a method to
plasticize PVC, making it easier to process

PVC/CPVC – rigid plastic pipes similar to PVC drain pipes but with thicker walls to
deal with municipal water pressure, introduced around 1970. PVC stands for
polyvinyl chloride, and it has become a common replacement for metal piping.

PVC should be used only for cold water, or for venting. CPVC can be used for hot
and cold potable water supply. Connections are made with primers and solvent
cements as required by code.
CHAPTER 4

Pipe Fittings

4.1Introduction:
This section discusses fittings primarily used in pressurized piping systems, though
there is some overlap with fittings for low-pressure or non-pressurized systems.
Specialized fittings for the latter setups are discussed in the next major
subsection.

A fitting is used in pipe systems to connect straight pipe or tubing sections, adapt

to different sizes or shapes and for other purposes, such as regulating (or
measuring) fluid flow. "Plumbing" is generally used to describe the conveyance of
water, gas, or liquid waste in domestic or commercial environments; "piping" is
often used to describe the high-performance (high-pressure, high-flow, high-
temperature or hazardous-material) conveyance of fluids in specialized
applications. "Tubing" is sometimes used for lighter-weight piping, especially that
flexible enough to be supplied in coiled form

4.2 Elbow:
An elbow is installed between two lengths of pipe (or tubing) to allow a change of
direction, usually a 90° or 45° angle; 22.5° elbows are also available. The ends may
be machined for butt welding, threaded (usually female), or socketed. When the
ends differ in size, it is known as a reducing (or reducer) elbow.
 A 90º elbow, also known as a "90 bend", "90 ell" or "quarter bend", attaches
readily to plastic, copper, cast iron, steel, and lead, and is attached to rubber with
stainless-steel clamps. Other available materials include silicone, rubber
compounds, galvanized steel, and nylon. It is primarily used to connect hoses to
valves, water pumps and deck drains. A 45º elbow, also known as a "45 bend" or
"45 ell", is commonly used in water-supply facilities, food, chemical and electronic
industrial pipeline networks, air-conditioning pipelines, agriculture and garden
production, and solar-energy facility piping.
Elbows are also categorized by length. The radius of curvature of a long-radius
(LR) elbow is 1.5 times the pipe diameter, but a short-radius (SR) elbow has a
radius equal to the pipe diameter. Short elbows, widely available, are typically
used in pressurized systems, and in physically tight locations.

Long elbows are used in low-pressure gravity-fed systems and other

applications where low turbulence and minimum deposition of entrained solids
are of concern. They are available in acrylonitrile butadiene styrene (ABS
plastic), polyvinyl chloride (PVC), chlorinated polyvinyl chloride (CPVC), and
copper, and are used in DWV systems, sewage, and central vacuumsystems.

4.3 Union:
A union, similar to a coupling, allows the convenient future disconnection of pipes
for maintenance or fixture replacement. In contrast to a coupling
requiring solvent welding, soldering, or rotation (for threaded couplings), a union
allows easy connection and disconnection, multiple times if needed. It consists of
three parts: a nut, a female end and a male end. When the female and male ends
are joined, the nut seals the joint by pressing the two ends tightly together.
Unions are a type of very compact flange connector.
Electric unions, with dielectric insulation, separate dissimilar metals (such as
copper and galvanized steel) to prevent galvanic corrosion. When two dissimilar
metals are in contact with an electrically conductive solution (ordinary tap water
is conductive), they form an electrochemical couple which generates a voltage
by electrolysis.
When the metals are in direct contact with each other, the electric current from
one to the other also moves metallic ions from one to the other; this dissolves
one metal, depositing it on the other. A dielectric union breaks the electrical path
with a plastic liner between its halves, limiting galvanic.
 

4.4 Nipple:
A nipple is a short stub of pipe, usually male-threaded steel, brass, chlorinated
polyvinyl chloride (CPVC), or copper (occasionally unthreaded copper), which
Connects two other fittings. A nipple with continuous uninterrupted threading is
known as a close nipple. Nipples are commonly used with plumbing and hoses.

4.5 Reducer:

A reducer allows for a change in pipe size to meet hydraulic flow requirements of

the system or adapt to existing piping of a different size. Although reducers are
usually concentric, eccentric reducers are used as needed to maintain the top- or
bottom-of-pipe level.
4.6 Coupling:
A coupling connects two pipes. If their sizes differ, the fitting is known as
a reducing coupling, reducer, or an adapter. There are two types of couplings:
"regular" and "slip". A regular coupling has a small ridge or stop internally, to
prevent over-insertion of a pipe, and thus under-insertion of the other pipe
segment (which would result in an unreliable connection).

A slip coupling (sometimes also called a repair coupling) is deliberately made

without this internal stop, to allow it to be slipped into place in tight locations,
such as the repair of a pipe that has a small leak due to corrosion or freeze
bursting, or which had to be cut temporarily for some reason.
Since the alignment stop is missing, it is up to the installer to carefully measure
the final location of the slip coupling to ensure that it is located correctly.

4.7 Tee:
Tee, the most common pipe fitting, is used to combine (or divide) fluid flow. It is
available with female thread sockets, solvent-weld sockets or opposed solvent-
weld sockets and a female-threaded side outlet. Tees can connect pipes of
different diameters or change the direction of a pipe run, or both. Available in a
variety of materials, sizes and finishes, they may also be used to transport two-
fluid mixtures.Tees may be equal or unequal in size of their three connections,
with equal tees the most common.
4.8Diverter tee:

This specialized type of tee fitting is used primarily in

pressurized hydraulicsystems, to divert a portion of the flow from the main line
into a side branch connected to a radiator or heat exchanger. The diverter tee is
designed to allow flow to continue in the main line, even when the side branch is
shut down and not calling for heat. Diverter tees have directional markings which
must be heeded; a tee installed backwards will function very poorly. Transfer the
flow.

4.9 Cross:
Crosses, also known as four-way fittings or cross branch lines, have one inlet and
three outlets (or vice versa), and often have solvent-welded socket or female-
threaded ends. Cross fittings may stress pipes as temperatures change, because
they are at the center of four connection points. A tee is steadier than a cross; it
behaves like a three-legged stool, and a cross behaves like a four-legged
stool. Geometrically, any three non-collinear points can self-consistently define a
plane; three legs are inherently stable, whereas four points overdetermine a
plane, and can be inconsistent, resulting in physical stress on a fitting.
4.10 Cap:
Caps, usually liquid- or gas-tight, cover the otherwise open end of a pipe.
A cap attaches to the exterior of a pipe, and may have a solvent-weld socket end
or a female-threaded interior. The exterior of an industrial cap may be round,
square, rectangular, U- or I-shaped, or may have a handgrip. If a solvent-weld cap
is used to provide for a future connection point, several inches of pipe must be
left before the cap; when the cap is cut off for the future connection, enough
pipes must remain to allow a new fitting to be glued onto it.

4.11 Plug:
A plug fits inside the pipe segment or fitting.

4.12 Barb:
A barb (or hose barb), which connects flexible hose or tubing to pipes, typically
has a male-threaded end which mates with female threads. The other end of the
fitting has a single- or multi-barbed tube—a long tapered cone with ridges, which
is inserted into a flexible hose. An adjustable worm drive screw clamp (or other
type of clamp) is often added, to keep the hose from slipping off the barbed tube.
Barb fittings can be made of brass for hot-water applications, and plastic may be
used for cold water; brass is considered more durable for heavy-duty use. The
barb fitting may be elbow-shaped or straight
 CHAPTER 5

Hydraulic fittings

5.1Introduction:

Hydraulic systems use high fluid pressure, such as the hydraulic

actuators for bulldozers and backhoes. Their hydraulic fittings are designed and
rated for much greater pressure than that experienced in general piping systems,
and they are generally not compatible with those used in plumbing. Hydraulic
fittings are designed and constructed to resist high-pressure leakage and sudden
failure
5.2Connection methods:
Much of the work of installing a piping or plumbing system involves making
leakproof, reliable connections, and most piping requires mechanical support
against gravity and other forces (such as wind loads and earthquakes) which
might disrupt an installation. Depending on the connection technology and
application, basic skills may be sufficient or specialized skills and professional
licensure may be legally required

5.3 Threaded pipe:

A threaded pipe has a screw thread at one or both ends for assembly. Steel pipe is
often joined with threaded connections; tapered threads are cut into the end of
the pipe, sealant is applied in the form of thread-sealing compound or thread seal
tape(also known as PTFE or Teflon tape) and the pipe is threaded into a threaded
fitting with a pipe wrench
Threaded steel pipe is widely used in buildings to convey natural
gas or propane fuel, and is a popular choice in fire sprinkler systems due to its
resistance to mechanical damage and high heat. Threaded steel pipe may still be
used in high-security locations; because it is more resistant to vandalism, more
difficult to remove, and its scrap value is lower than copper or brass Assembling
threaded steel pipe takes skill and planning to allow lengths of pipe to be screwed
together in sequence. Most threaded-pipe systems require the use of strategically
located pipe-union fittings in final assembly. Threaded steel pipe is heavy, and
requires adequate attachment to support surfaces. Despite its thick walls steel
pipe is no longer preferred for conveying drinking water, because corrosion can
cause leakage especially at threaded joints, and deposits on internal surfaces will
eventually restrict flow.
5.4Solvent welding:
A solvent is applied to PVC, CPVC, ABS or other plastic piping to partially dissolve
and fuse the adjacent surfaces of piping and fitting. Solvent welding is usually
used with a sleeve-type joint to connect pipe and fittings made of the same (or
compatible) material.

Unlike metal welding, solvent welding is relatively easy to perform (although care
is needed to make reliable joints). Solvents typically used for plastics are
usually  and may be carcinogenic and flammable, requiring adequate ventilation.
5.5Soldering:
Make a solder connection, a chemical flux is applied to the inner sleeve of a joint
and the pipe is inserted. The joint is then heated using a propane or MAPP
gas torch, solder is applied to the heated joint and the molten solder is drawn into
the joint by capillary action as the flux vaporizes. "Sweating" is a term sometimes
used to describe the soldering of pipe joints.

Where many connections must be made in a short period of time (such as

plumbing of a new building), soldering is quicker and less expensive joinery than
compression or flare fittings. A degree of skill is needed to make a number of
reliable soldered joints quickly. If flux residue is thoroughly cleaned, soldering can
produce a long-lasting connection at low cost. However, the use of an open flame
for heating joints can present fire and health hazards to building occupants, and
requires adequate ventilation.

5.6 Welding:
The welding of metals differs from soldering and brazing in that the joint is made
without adding a lower-melting-point material (e.g. solder); instead, the pipe or
tubing material is partially melted and the fitting and piping are directly fused.
This generally requires that the piping and fitting are the same (or compatible)
material. Skill is required to melt the joint sufficiently to ensure good fusion, while
not deforming or damaging the pieces being joined.
Properly welded joints are considered reliable and durable. Pipe welding is often
performed by specially licensed workers whose skills are retested periodically. For
critical applications, every joint is tested with nondestructive methods. Because of
the skills required, welded pipe joints are usually restricted to high-performance
applications such as shipbuilding, and in chemical and nuclear reactors

Adequate ventilation is essential to remove metal fumes from welding operations,

and personal protective equipment must be worn. Because the high
temperatures during welding can often generate intense ultraviolet light, dark
goggles or full face shields must be used to protect the eyes. Precautions must
also be taken to avoid starting fires caused by stray sparks and hot welding debris.

5.7 Compression fittings:

Compression fittings (sometimes called "lock-bush fittings") consist of a tapered,

concave conical seat; a hollow, barrel-shaped compression ring (sometimes called
a ferrule); and a compression nut which is threaded onto the body of the fitting
and tightened to make a leakproof connection. They are typically made of brass
or plastic, but stainless steel or other materials may be used.
5.8 Flare fittings:
Flared connectors should not be confused with compression connectors, with
which they are generally not interchangeable. Lacking a compression ring, they
use a tapered conical shaped connection instead. A specialized flaring tool is used
to enlarge tubing into a 45º tapered bell shape matching the projecting shape of
the flare fitting. The flare nut, which had previously been installed over the
tubing, is then tightened over the fitting to force the tapered surfaces tightly
together. Flare connectors are typically made of brass or plastic, but stainless
steel or other materials may be used.
Although flare connections are labor-intensive, they are durable and reliable.
Considered more secure against leaks and sudden failure, they are used
in hydraulic brake systems, and in other high-pressure, high-reliability
applications

5.9 Flange fittings:

Flange fittings are generally used for connections to valves, inline instruments or
equipment nozzles. Two surfaces are joined tightly together with
threaded bolts, wedges, clamps, or other means of applying
high compressive force. Although a gasket, packing, or O-ring may be installed
between the flanges to prevent leakage, it is sometimes possible to use only
special grease or nothing at all (if the mating surfaces are sufficiently precisely
formed). Although flange fittings are bulky, they perform well in demanding
applications such as large water supply networks and hydroelectric systems.

A weld neck flange is joined to a piping system by butt welding. Although its long
neck (or hub) makes it expensive, it reduces mechanical stress on piping by
distributing stress between the base of the flange and the wall at the weld.
Turbulence and erosion are reduced due to the matching size of the pipe and
flange a socket flange appears similar to a slip-on flange, but its bore is counter-
bored to accept pipe. A fillet weld around the hub of the flange attaches the
flange to the pipe, with an interval weld added in high-stress applications. It is
most frequently used in high-pressure systems, such as hydraulic and steam lines
 A lap-joint flange is similar to a slip-on, with room at the intersection of the
bore and the flange face for a lap stub end. The face of the stub end conforms to
the gasket face of the flange. It is used where sections of piping need to be
dismantled quickly and easily for inspection or replacement,

5.10 Mechanical fittings:

Manufacturers such as Victaulic and Grinnell produce sleeve-clamp fittings which
are replacing many flange connections. They attach to the end of a pipe segment
via circumferential grooves pressed (or cut) around the end of the pipe to be
joined. They are widely used on larger steel pipes, and can also be used with
other materials.

The chief advantage of these connectors is that they can be installed after cutting
the pipe to length in the field. This can save time and considerable expense
compared to flange connections, which must be factory- or field-welded to pipe
segments. However, mechanically fastened joints are sensitive to residual and
thickness stresses caused by dissimilar metals and temperature changes A
grooved fitting, also known as a grooved couplinghas four elements: grooved
pipe, gasket, coupling housing, and nuts and bolts. The groove is made by cold-
forming (or machining) a groove at the end of a pipe.
A gasket encompassed by coupling housing is wrapped around the two pipe ends,
with the coupling engaging the groove; the bolts and nuts are tightened with
a socket or impact wrench. The installed coupling housing encases the gasket and
engages the grooves around the pipe to create a leakproof seal in a self-
restrained pipe joint. There are two types of grooved coupling; a flexible coupling
allows a limited amount of angular movement, and a rigid coupling does not allow
movement and may be used where joint immobility is required (similar to a flange
or welded joint).